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Japan's Strategic Countermeasures against the Pirates of the Seas


By Daisuke Komatsu

Towards the end of 2023 and the beginning of 2024, a series of piracy incidents, including the capture of cargo ships and tankers, occurred in the waters around the Gulf of Aden, near Yemen and Somalia. Additionally, there has been an increase in pirate attacks in Southeast Asian waters in recent years, posing significant threats to the safety of nearby vessels and raising major concerns for economic security. In light of this background, this journal article aims to elucidate Japan's counter-piracy measures.

Tracing back the history of piracy in Japan, references to pirates can be found as early as the latter half of the 5th century in the "Nihon Shoki" (Chronicles of Japan). Notably, during the late 15th century and the Sengoku period (Warring States period), pirate groups known as the "Murakami KAIZOKU,” a group functioning both as pirates and a naval force, were frequently active in the Seto Inland Sea. In more contemporary times, incidents such as the 1999 attack on the Arlanda Rainbow, which was en route from Indonesia to Japan, and the 2005 attack on the Japanese-flagged ocean-going tugboat Idaten in the northwestern part of the Strait of Malacca, have occurred.


Globally, piracy has been a longstanding maritime security threat throughout history, evident from occurrences in the Roman Empire era, the Vikings in the 8th century, privateers during the Age of Discovery, the Barbary pirates in North Africa, and pirates in the Caribbean and Indian Oceans.

Revisiting the definition of piracy, according to Article 101 of the United Nations Convention on the Law of the Sea, piracy consists of:


(a) Any illegal acts of violence, detention, or depredation for private ends by the crew or passengers of a private ship or aircraft against:


(i) Another ship or aircraft, or persons or property on board in the high seas;

(ii) A ship, aircraft, persons or property in a place outside the jurisdiction of any state.


(b) Voluntary participation in the operation of a ship or aircraft with knowledge that it is a pirate ship or aircraft.


(c) Incitement or intentional facilitation of acts defined in subparagraph (a) or (b).

Article 105 of the same convention outlines that any state may seize a pirate ship or aircraft, or a ship taken by piracy and under the control of pirates, and arrest the persons and seize the property on board in the high seas or any other place outside the jurisdiction of any state. The courts of the state which carried out the seizure may decide upon the penalties to be imposed, and, with due regard to the rights of bona fide third parties, may determine the action to be taken with respect to the ship, aircraft, or property.

In essence, piracy is robbery conducted on the high seas and is considered a universal enemy against which any state may act. Pirate acts occurring within territorial waters of coastal states, as opposed to the high seas, are defined as armed robbery at sea.

Considering the above, an overview of Japan's counter-piracy measures is provided. As an island nation with low food and energy self-sufficiency rates, Japan relies heavily on maritime transport routes for 99.5% of its imported resources essential for maintaining economic activities and social life. Thus, protecting merchant vessels from piracy is a lifeline for the country.


Created by the author using freely available resources.

Direct enforcement in pirate-infested waters like the Malacca and Singapore Straits was not feasible for Japan due to territorial limitations. Consequently, the Japan Coast Guard led the adoption of the "Asian Anti-Piracy Challenges 2000" at this conference, proposing measures such as mutual visits of patrol ships, joint training exercises, continuous expert meetings, and conducting seminars on maritime crime control. Initiatives also included accepting students for maritime crime seminars at the Japan Coast Guard Academy and JICA, dispatching long-term JICA experts, and supporting capacity building through joint training with coastal countries.

These efforts led to a significant reduction in piracy incidents in Southeast Asia after 2004. However, piracy in Somalia, particularly around the Gulf of Aden, surged post-2007. A notable incident in February 2007 involved the hijacking of the MV Rozen, a cargo ship chartered by the World Food Programme for humanitarian aid to Somalia, leading to the abduction of 12 crew members. This incident underscored the international community's need to collaborate in combating piracy in the region.


Created by the author using data sourced from the International Maritime Bureau (IMB) reports.


In contrast to the pirates in Southeast Asia, those operating in the Gulf of Aden and off the coast of Somalia are characterized by their heavy armament, organized operations, and operations in a broad maritime area far from land. Notably, they often kidnap entire crews and ships, demanding ransoms, rather than just looting goods or cargoes. Since 1991, Somalia has been in a state of anarchy, lacking a functional government capable of combating piracy, differentiating it from the situation in Southeast Asia.

With the passing of multiple United Nations Security Council resolutions in 2008, the CTF151 (Combat Task Force) fleet, predominantly comprising EU and NATO member states, was dispatched to protect ships in these waters, leading to an increase in the forceful suppression of pirates. The United States also joined the efforts with its Navy and Coast Guard as part of the combined maritime task force.

Recognizing that about 10% of the vessels transiting the Gulf of Aden annually are Japan-related, and to fulfill its role as a responsible nation in the United Nations, Japan acknowledged the importance of counter-piracy measures in the region. The Japan Coast Guard, tasked with protecting lives and property from piracy and maintaining security, faced challenges in collaborating with CTF151 and exercising jurisdiction over maritime crimes in international waters.


However, dispatching the Japan Maritime Self-Defense Force (JMSDF) was considered. Under the Self-Defense Forces Law Article 82, JMSDF's maritime security operations are primarily limited to protecting Japanese lives or property, presenting challenges in guarding non-Japanese vessels like those protected by CTF151.

To address these challenges, Japan legislated the Anti-Piracy Measures Law in June 2009. This law enabled the Japan Coast Guard to exercise jurisdiction over piracy, considered a crime in international waters, and allowed JMSDF escort vessels to guard foreign-flagged ships in coordination with CTF151. A significant feature of this law is that it defined piracy as a crime within Japan's legal system for the first time, allowing for the protection of not just Japanese vessels but also foreign ships. The law also permitted preventive actions against piracy, such as firing warning shots when pirates approached civilian vessels. This legislation marked a milestone in asserting jurisdiction in international waters, a domain typically governed by the principle of flag state jurisdiction.


JMSDF has since been conducting escort operations and surveillance activities, regardless of the ships' nationality, based on their requests in the Gulf of Aden, with significant collaboration from the Japan Coast Guard. Coast Guard officers, deployed on JMSDF ships, play a crucial role in enforcing the Anti-Piracy Measures Law. This joint operation ensures effective law enforcement and escort operations. From 2013, Japan has participated in CTF151, further intensifying its anti-piracy measures. These efforts have significantly reduced piracy incidents around Somalia. Japan continues to support the enhancement of maritime security capabilities in Somalia and neighboring countries and aims for the fundamental resolution of the piracy issue, contributing to the reconstruction and stabilization of Somalia.


Moreover, some analysts suggest that the piracy incidents mentioned earlier might be linked to 2023 Israel-Hamas War, , underscoring the necessity for continued international cooperation and efforts to address the root causes of piracy for ensuring maritime security in the region.

January 2024

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